Urinary Tract Part Deux

URETER 3 layers:3 layers: Mucosa = epithelium (TRANSITIONAL) plus some underlying CT, that you all know is called the LAMINA PROPRIAMucosa = epithelium (TRANSITIONAL) plus some underlying CT, that you all know is called the LAMINA PROPRIA Muscularis = has…. muscle! Imagine that.Muscularis = has…. muscle! Imagine that. 2-3 bundles of smooth muscle to be exact depending where you are in the journey of the ureter2-3 bundles of smooth muscle to be exact depending where you are in the journey of the ureter Adventitia = just like every other adventitia you have enjoyed this year, its just some CT, can have blood vessels and whatnot in itAdventitia = just like every other adventitia you have enjoyed this year, its just some CT, can have blood vessels and whatnot in it

Ureter, in all its glory

This look familiar?

It should! It’s the transitional epithelium of the mucosa in the ureterIt’s the transitional epithelium of the mucosa in the ureter A nice memory of the fun we all had in block oneA nice memory of the fun we all had in block one

Ureter cont’d How do you tell it apart from the urethra?How do you tell it apart from the urethra?

Ureter vs. urethra Because the urethra is shaped like a half moon/crescent and this isntBecause the urethra is shaped like a half moon/crescent and this isnt Because the epithelium of the ureter is transitional epithelium and the urethra can be pseudostratified columnar or stratified squamous or transitionalBecause the epithelium of the ureter is transitional epithelium and the urethra can be pseudostratified columnar or stratified squamous or transitional Because you often get a nice glimpse of vagina when they show you urethra on the glass slideBecause you often get a nice glimpse of vagina when they show you urethra on the glass slide

Not half moon – I’m thinking more STAR shaped Half moon….. kinda. Whatever.

ureter Lets talk about the muscularisLets talk about the muscularis Tell me about how the layers are orientedTell me about how the layers are oriented

Muscle of the ureter, everyone’s favorite dinnertime subject Well rachel, at the top of the ureter there are only two: inner longitudinal and outer circularWell rachel, at the top of the ureter there are only two: inner longitudinal and outer circular And at the lower 1/3 part of the ureter there can be THREE WHOLE LAYERS, with the additional layer being outer longitudinal: so inner longitudinal, middle circular, outer longitudinalAnd at the lower 1/3 part of the ureter there can be THREE WHOLE LAYERS, with the additional layer being outer longitudinal: so inner longitudinal, middle circular, outer longitudinal

Inner longitudinal Outer circular

Bladder Same layout as ureter: mucosa, muscularis, adventitiaSame layout as ureter: mucosa, muscularis, adventitia Nice example of transitional epithelium – hello block one!Nice example of transitional epithelium – hello block one! Is mucosa thicker in bladder or ureter?Is mucosa thicker in bladder or ureter?

bladder In the bladder!In the bladder! This is sensible because the bladder has to hold more pee than the ureter, thus needs stronger wallsThis is sensible because the bladder has to hold more pee than the ureter, thus needs stronger walls

Where are we?

Well, it is transitional epithelium, yes? So you know it could be from the bladder…… OR the ureter OR the urethra. All three can have transitional. However, because I took this directly from your online lab manual I know it is bladder.Well, it is transitional epithelium, yes? So you know it could be from the bladder…… OR the ureter OR the urethra. All three can have transitional. However, because I took this directly from your online lab manual I know it is bladder.

bladder How many layers of smooth muscle are there in the muscularis of the bladder?How many layers of smooth muscle are there in the muscularis of the bladder?

THREE layers of bundled smooth muscleTHREE layers of bundled smooth muscle

ONETWO THREE

Serosa vs. adventitia Whats this serosa everyone is talking about?Whats this serosa everyone is talking about? Well, in the BLADDER ONLY, if there is a layer of mesothelium OUTSIDE THE ADVENTITIA, then it’s a serosaWell, in the BLADDER ONLY, if there is a layer of mesothelium OUTSIDE THE ADVENTITIA, then it’s a serosa What a nice written question this would make!What a nice written question this would make!

Girl power Urethra is cooler than the ureter because it can have THREE different kinds of epithelium: transitional, pseudostratified columnar and stratified squamous.Urethra is cooler than the ureter because it can have THREE different kinds of epithelium: transitional, pseudostratified columnar and stratified squamous. Why don’t you tell me where each of these are found in the path of the urethraWhy don’t you tell me where each of these are found in the path of the urethra

Uretha epithelium – another good dinnertime topic Well at the top you have transitional, then in the middle you have pseudostratified columnar, and at the bottom you have stratified squamous just like in the…… VAGINA!!Well at the top you have transitional, then in the middle you have pseudostratified columnar, and at the bottom you have stratified squamous just like in the…… VAGINA!!

Pseudostratified epithelium of urethra

I personally think the urethra looks nothing like a half moon or crescent. I always thought it looked more like a gecko. You be the judge……I personally think the urethra looks nothing like a half moon or crescent. I always thought it looked more like a gecko. You be the judge……

My theory Gecko mouth Gecko legs Gecko tail

Or half moon? = = I think not

urethra What does the uretha have in the epithelium that ureter does not?What does the uretha have in the epithelium that ureter does not?

urethra Glands, beotchGlands, beotch

urethra What else does the lamina propria (remember, with the epithelium makes up the mucosa) have?What else does the lamina propria (remember, with the epithelium makes up the mucosa) have?

1. Venous plexus1. Venous plexus 2. Mucus glands (of Littre – as if you care)2. Mucus glands (of Littre – as if you care) So in the urethra there are intraepithelial mucus glands and also more mucus glands in the lamina propriaSo in the urethra there are intraepithelial mucus glands and also more mucus glands in the lamina propria

More urethra fun! So you have a muscularis here as well. Speak to me about the layers and their orientation.So you have a muscularis here as well. Speak to me about the layers and their orientation.

Well, like the urethra, inner longitudinal and outer circular, but if you are down far enough (you would see what epithelium here??? Simple squamous or pseudo) there can be a outer circular sphincter of skeletal muscle (vs. smooth muscle that you see everywhere else)Well, like the urethra, inner longitudinal and outer circular, but if you are down far enough (you would see what epithelium here??? Simple squamous or pseudo) there can be a outer circular sphincter of skeletal muscle (vs. smooth muscle that you see everywhere else)

Venous plexus in lamina propria Inner long. muscle Outer circular muscle

adventitia Continuous with vagina, which you often see RIGHT NEXT TO IT – this is KEY if you get a glass slide. You see vag, its gotta be urethra.Continuous with vagina, which you often see RIGHT NEXT TO IT – this is KEY if you get a glass slide. You see vag, its gotta be urethra.

gecko vag Shared adventitia

QUIZ TIME

Well it’s the urethra because it looks like a geckoWell it’s the urethra because it looks like a gecko Its in the lamina propriaIts in the lamina propria MUCUS GLAND OF LITTREMUCUS GLAND OF LITTRE

Inner longitudinal smooth muscle bundle in the ureterInner longitudinal smooth muscle bundle in the ureter

Red area is???

Lamina propria!Lamina propria! Remember…… lamina propria + epithelium = mucosaRemember…… lamina propria + epithelium = mucosa So if they circle both you say MUCOSA!So if they circle both you say MUCOSA!

What is this? How do you know?

URETERURETER Star-shapedStar-shaped Transitional epitheliumTransitional epithelium

What is this?

Urethra! Crescent/gecko/half moon shapeCrescent/gecko/half moon shape

What kind of epithelium

Well you know it’s the ureter because its star shapedWell you know it’s the ureter because its star shaped So it has to be transitionalSo it has to be transitional

hmmmmm Well it looks like fat, right?Well it looks like fat, right? Is fat in the mucosa?Is fat in the mucosa? nono Is fat in the muscularis?Is fat in the muscularis? nono Is fat in the adventitia?Is fat in the adventitia? YES! Adventitia is just a bunch of loosish CT and can have vessels and fat in it!YES! Adventitia is just a bunch of loosish CT and can have vessels and fat in it! So I would say “adipose tissue in the ureter adventitia”So I would say “adipose tissue in the ureter adventitia”